Developmental educational-rehabilitation assessment can be defined as an organized process of data collection, analysis and processing for the purpose of screening, diagnostics, determining developmental status, planning and programming rehabilitation work, as well as for monitoring and assessing the child's progress under treatment. Therefore, the assessment implies a fundamental, but at the same time complex and inseparable part of the rehabilitation process of children with disabilities. In practice, different types of assessments exist and are applied. According to the authors McLoughlin and Lewis (2009), the basic division is that of formal and informal assessment. Formal assessment implies the use of standardized measuring instruments, ie instruments based on norms created to determine the exact position of an individual in relation to the normative group. Its main purpose is to compare the results of the subjects with other subjects and display them on the Gaussian curve separately about the instruments, it is used for screening and diagnostics. On the other hand, informal methods are used to determine the current performance of the respondents on certain tasks that monitor the child's progress during the rehabilitation program as a function of time. They are less structured than formal assessments, and the results obtained on them do not serve to compare an individual with a normative group. However, given the direct association of informal methods assessed with the curriculum or rehabilitation program, the usability of the results and data that can be obtained is potentially of high importance (McLoughlin and Lewis, 2009). The aim of this thesis is to investigate a comprehensive review of recent professional and scientific literature on educational and rehabilitation assessment of children with disabilities and compare it with existing assessment practice in the Republic of Croatia. Also, a study was conducted which examined the quality factors of educational-rehabilitation assessment, type and content of assessment, as well as the challenges faced by educational rehabilitators in this process and recommendations for improving the existing practice of educational-rehabilitation assessment in Croatia. For this purpose, the sample of educational rehabilitators filled in the Questionnaire for multidimensional analysis of educational-rehabilitation assessment created for research purposes. The questionnaire consists of 95 particles of closed, semi-open and open type, which is why the processing and interpretation of the obtained results was carried out on the basis of qualitative and quantitative analysis.